Consolidated Statements of Comprehensive Income (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Statement of Comprehensive Income [Abstract]
Net income	$ 18,034	$ 13,754	$ 6,428	$ 21,325
Other comprehensive (loss) income:
Unrealized (loss) gain on available for sale securities	(10)	66	(5)	(23)
Foreign currency translation adjustment	(672)	(936)	(913)	(634)
Other comprehensive (loss)	(682)	(870)	(918)	(657)
Comprehensive income	$ 17,352	$ 12,884	$ 5,510	$ 20,668